HEALTH chiefs today issued an urgent warning after two York people developed poisoning from the deadly botulism bug.

One of the patients is said to be responding to treatment, but the other was said to be still in hospital. Both are intravenous drug users who are believed to have developed wound botulism from a contaminated batch of heroin.

Health officials today warned people to contact a doctor immediately if they developed symptoms, which initially include blurred vision, difficulty swallowing, diarrhoea and vomiting.

If botulism is left untreated, paralysis can spread through the arms, legs, trunk and respiratory muscles.

If the onset is very rapid there may be not symptoms before sudden respiratory paralysis occurs, which can lead to death.

People suffering from botulism may need to have their breathing maintained artificially by a breathing machine until the effect of the toxin has passed off, sometimes for as long as four weeks.

The overall death rate for botulism is 50 to 70 per cent, but those who survive the respiratory paralysis can recover completely.

Dr Ebere Okereke, consultant in communicable disease control at the North Yorkshire Health Protection Agency, said: "The disease can be fatal. Symptoms often begin with blurred vision and difficulty in swallowing and speaking, but diarrhoea and vomiting can occur.

"Symptoms can lead to further problems with vision and paralysis.

"If you develop swelling, redness or pain where you have injected yourself, or if pus collects under the skin, contact a doctor immediately."

Health officials have issued a list of precautions in an effort to reduce the risk of contracting the disease.

They urged drug users to smoke heroin rather than injecting, and not to share needles, syringes, or other drugs paraphernalia.

Updated: 09:26 Saturday, May 15, 2004